Remove Depends(get_session) from POST /{id}/update endpoint to prevent database connections from being held during embedding API calls (1-5+ seconds).
All database operations (get_knowledge_by_id, has_access, has_permission, update_knowledge_by_id, get_file_metadatas_by_id) manage their own short-lived sessions internally, releasing connections before and after the slow embed_knowledge_base_metadata() call.